The present invention relates to improved pharmaceutical formulations.
Many compounds that can be injected intravascularly into animal and human patients for a beneficial effect have the undesirable hazardous side effect of causing ulceration at the injection site as a result of extravasation. Extravasation is strictly defined as the forcing of fluid out of a blood or lymph vessel into the surrounding or perivascular tissue. More broadly defined, extravasation may be said to occur when an injection solution and blood or serum combined with an injection solution leaks out of a blood vessel during intravascular administration of the solution or subsequent thereto, at the site of injection, or when the injection solution is accidentally injected into tissue surrounding a blood vessel. Such extravasation may occur as a result of accidentally failing to properly insert a needle for the intravascular administration of a solution into the lumen of a blood vessel. It may also occur by accidentally inserting a needle entirely through a blood vessel intended for intravascular administration. In addition, leakage of solution from a blood vessel may occur if a blood vessel is too small for the rate and volume of injection solution being injected into the blood vessel. Lastly, leakage of solution from a blood vessel may occur if the blood vessel has been damaged or eroded by prior injection or other trauma.
Extravasation of certain intravasuclarly administered compounds may lead to formation of a deep, spreading and painful ulcer which may require surgical extirpation of the affected tissue. Skin grafting is frequently required to repair and reconstruct the resulting wound. Another complication of such intravascularly administered compounds is that they are irritants causing irritation of the lining of the blood vessel into which they are injected. This irritation may be accompanied by pain at the site of injection or along the length of the blood vessel. In addition the irritation may lead to reduced patency of the blood vessel and in some cases may induce the formation of blood clots in the affected blood vessel leading to a risk of gangrene or emboli.
Not all injection solutions cause ulceration as a result of extravasation; however; many pharmaceutical compounds injected for particular chemotherapeutic effects in many therapeutic categories have this presently unavoidable side effect. Pharmaceutical compounds having this side effect are well known to those skilled in the art of administration of such compounds to patients and animal subjects. The side effects of such drugs are collected in a number of publication including the Physicians Desk Reference published yearly by Medical Economics Data, a division of Medical Economics Company Inc., Montvale N.J. 07645 USA and the United States Pharmacopeia Drug Information published and supplemented by the Untied States Pharmacopeial Convention, Inc 12601 Twinbrook Parkway, Rockville, Md. 20852, USA. Similar volumes are published else where in various countries of the world.
Among the pharmaceutical compounds that cause extravasation associated ulceration are cytotoxic compounds which are administered to patients and animal subjects for the purpose of manifesting a specific cytotoxic effect. Such cytotoxic compounds include many anticancer or antineoplastic compounds. These compounds may be synthetic chemical compounds, such as nitrogen mustard derivatives such as mechlorethamine, plant alkaloids such as vincristine and vinblastine, alkylating agents such as dacarbazine and streptozocin or microbially produced and purified or partially purified antibiotics. Cytotoxic antibiotics include those administered as anti-cancer agents, such as mitomycin, bleomycin, daunorubicin, doxorubicin, plicamycin and dactinomycin. In addition antifungal antibiotic agents such as amphoteracin B can cause ulceration associated with extravasation. Furthermore, therapeutic compounds which are not administered to achieve a specific cytotoxic effect may also result in extravasation associated ulceration. For example certain sedative compounds when injected intravasculary (IV) can cause severe ulceration if extravasation occurs. Such sedative compounds include but are not limited to benzodiazapine compounds including diazepam. Thus, there is a long felt need For safer formulations of injectable pharmaceutical compounds to reduce or eliminate ulceration resulting from extravasation.
Pharmaceutical preparations containing cyclodextrin are known. Human sex hormones including, estradiol-, progesterone- and testosterone-hydrophilic cyclodextrin derivatives, especially hydroxypropyl cyclodextrin suitable for oral mucosal or rectal mucosal Administration are disclosed in U.S. Pat. No. 4,596,795. These preparations are disclosed as increasing the circulating half life of the hormone through elimination of absorbance via the gastrointestinal tract and consequent removal by hepatic clearance. There is no disclosure of complexes that reduce local ulceration or irritation at an injection site.
U.S. Pat. No. 4,727,064 disclosed pharmaceutical preparations consisting generally of a drug with a substantially low water solubility and an amorphous water soluble cyclodexrin-based mixture having improved dissolution properties and absorption by the body. The solutions of amorphous water soluble cyclodextrin are disclosed as non-irritating topically, and having low toxicity, both systemic and local, when applied parenterally. None of the amorphous cyclodextrin-drug mixtures disclose in the specification or claims discloses a complex including a drug that causes ulceration when extravasted and there is no disclosure concerning reduction of ulceration as a result of administering the drug in a complex with an amorphous cyclodextrin complex.
A variety of improvements in the characteristics of pharmaceutical complexes including various cyclodextrins and cyclodextrin derivatives are disclosed in the following United States patents, but none of them disclose the reduction in extravasation-associated ulceration, or irritation through the formation of complexes of cyclodextrin and pharmaceutical compounds: Noda et al., U.S. Pat. No. 4,024,223 methyl salicylate; Szejtli et al U.S. Pat. No. 4,228,160 indomethacin; Hyashi et al., U.S. Pat. No. 4,232,009 xcfx89-halo-PGI2 analogs; Matsumoto et al., U.S. Pat. No. 4,351,846 3-hydroxy and 3-oxo prostaglandin analogs; Yamahira et al., U.S. Pat. No. 4,353,793, bencyclane fumarate; Lipari, U.S. Pat. No. 4,383,992 steroids-corticosteroids, androgens anabolic steroids, estrogens, progestagens; Nicolau, U.S. Pat. No. 4,407,795 P-hexadecyla-ninobenzoic acid sodium salt; Tuttle, U.S. Pat. No. 4,424,209 3,4-diisobutyryloxy-N-{3-(4-isobuttyryloxyphenyl)-1-methyl-n-propyl]-xcex2-phenethylamine; Tuttle, U.S. Pat. No. 4,425,336, 3,4-dihydroxy-N-[3-(4-hydroxyphenyl)-1-methyl-n-propyl]-xcex2-phenethylamine; Wagu et al., U.S. Pat. No. 4,438,106 fatty acids EPA and DHA; Masuda et al., U.S. Pat. No. 4,474,881 2-(2-fluoro-4-biphenyl)propionic acid or salt; Shinoda et al., U.S. Pat. No. 4,478,995 acid addition salt of (2xe2x80x2-benzyloxycarbonyl)phenyl trans-4-guanidinomehtylcyclohexanecaboxylate; Hyashi et al., U.S. Pat. No. 4,479,944 Prostaglandin I2 analog; Hayashi et al., U.S. Pat. No. 4,479,966, 6,9-methano-prostaglandin I2 analogs; Harada et al., U.S. Pat. No. 4,497,803 lankacidin-group antibiotic; Masuda U.S. Pat. No. 4,499,085 prostoglandin analog; Szejtli et al., U.S. Pat. No. 4,524,068 piperonyl butoxide; Jones, U.S. Pat. No. 4,555,504 cardiac glycoside; Uekama et al., U.S. Pat. No. 4,565,807 pirprofen; Ueda et al., U.S. Pat. No. 4,575,548 2-nitroxymethyl-6-chloropyridine; Ohwaki et al., U.S. Pat. No. 4,598,070 tripamide anti-hypertensive; Chiesi et al., U.S. Pat. No. 4,603,123 piroxicam (feldene); Hasegawa et al., U.S. Pat. No. 4,608,366 monobenzoxamine; Hiari et al., U.S. Pat. No. 4,659,696 polypeptide; Szejtili et al., U.S. Pat. No. 4,623,641 Prostoglandin I2 methyl ester; Ninger et al., U.S. Pat. No. 4,663,316. unsaturated phosphorous containing antibiotics including phosphotrienin; Fukazawa et al., U.S. Pat. No. 4,675,395 hinokitol; Shimizu et al., U.S. Pat. No. 4,728,509 3-amino-7-isopropyl-5-oxo-5H-[1]-benzopyrano[2,3-b]pyridine-3-carboxcylic acid; Shibani et al., U.S. Pat. No. 4,728,510 milk component Karl et al U.S. Pat. No. 4,751,095 aspartame.
Among the above-mentioned patents, several indicate that complexes of cyclodextrin with drug substances improve side effects of the drug substance. Szejtli et al., U.S. Pat. No. 4,228,160 disclosed that the frequency and severity of gastric and duodenal erosion and ulceration in rats caused by indomethecin is improved in an oral formulation of a complex of xcex2-cyclodextrin: indomethacin in a 2:1 ratio, but is not improved and in fact worsens in the same oral formulation of a complex of xcex2-cyclodextrin: indomethacin in a 1:1 ratio.
Shirmazu et al., U.S. Pat. No. 4,352,793 discloses that a formulation wherein bencyclane fumarate an anti-convulsive compound and xcex2-cyclodextrin or xcex3-cyclodextrin yield a complex in which the bencyclane fumarate is an inclusion compound. These complexes, when formulated as a liquid suitable for oral administration were claimed to be less irritating in an isotonic buffered pH 7 solution when administered as drops to the eyes of rabbits, as compared to bencyclane fumarate drops at the same drug concentration. Shimazu et al., also discloses that similar complexes dissolved in rabbit blood in vitro yielded reduced hemolysis as compared to equal concentrations of bencyclane fumarate alone mixed with rabbit blood. There was no indication that this compound is cytotoxic or causes ulceration or irritation of the surrounding tissue when extravasated during or after injection.
Masuda et al., U.S. Pat. No. 4,478,811 disclose ophthalmic formulations of xcex2- or xcex3-cyclodextrin complexes of the nonsteroidal anti-inflammatory compound fluoro-bi-phenylacetic acid which are less irritating and painful than the same formulations of fluoro-bi-phenyl acetic acid alone. There was no indication that this compound is cytotoxic or causes ulceration of the surrounding tissue when extravasated during for after injection.
Shinoda et al., U.S. Pat. No. 4,478,995 disclose complexes of xcex1-, xcex2- and xcex3-cyclodextrin and acid addition salts of (2-benzyloxycarbonyl)phenyl trans-4-guanidinomehtylcyclo-hexanecaboxylate, and enzyme inhibitor having anti-gastric and duodenal ulcer activity. The complexes were administered orally and were more active in preventing ulceration than oral administration of acid addition salts of (2xe2x80x2-benzyloxycarbonyl)phenyl trans-4-guanidinomehtylcyclo-hexanecaboxylate alone in solution. No preparation suitable for intravenous injection were disclosed and there was no indication that this compound is cytotoxicor causes ulceration of the surrounding tissue when extravasated during for after injection.
Uekama et al., U.S. Pat. No. 4,565,807 discloses complexes of xcex1-, xcex2- and xcex3-cyclodextrin, pirprofen and a pharmaceutically acceptable base. Piprofen is an analgesic and anti-inflammatory compound which is bitter and can cause irritation to the gastrointestinal tract. The complexes disclosed in the patent have improved less bitter taste and are less gastrointestinal irritating than the un-complexed compound piprofen. No preparation suitable for intravenous injection were disclosed and there was no indication that this compound is cytotoxic or causes ulceration of the surrounding tissue when extravasated during for after injection.
Bekers, O., et al.,xe2x80x9cStabilization of mitomycins on complexation with cyclodextrins in aqueous acidic mediaxe2x80x9d International Journal of Pharmaceutics, 53 (1989) 239-248 describes the investigation of stabilization of mytomycin-C and several related mitomycins by formation of a complex with cyclodextrin. The authors indicate that at the pH ranges studied xcex1- and xcex2-cyclodextrin as sell as heptakis-(2,6,-di-O-methyl)-xcex2-cyclodextrin and (dimethyl-xcex2-cyclodextrin have no influence on stabilization of mitomycin-C pH degradation. xcex3-cyclodextrin is reported as having measurable stabilizing effect on mitomycin in acidic media at pH above 1. There is no suggestion that stabilization of mitomycin-C from acidic degradation in aqueous media by complexation with xcex3-cyclodextrin is or can be related to amelioration of ulceration or irritation caused by mitomycin when administered to a patient.
Bodor U.S. Pat. No. 5,024,998 and Bodor U.S. Pat. No. 4,983,586 disclose a series of compositions comprising complexes of :Beta hydroxypropylcyclodextrin (HPCD)-complexed to a difficult to solubilize drug, or HPCD complexed to a drugxe2x80x94which has first been complexed to a specific class of drug carriers characterized as redox drug carriers. The complex of drug and redox carrier is itself difficult to solubilize and is highly lipophilic due to the presence of pyridine derivatives as part of the redox carrier complex. Bodor ""998 and ""586 further claim that a solution of 20 to 50% hydroxypropylcyclodextrin-and lipophilic drug-redox carrier complex or 20 to 50% hydroxypropylcyclodextrin-and lipophilic and or water labile drug is useful in a method of xe2x80x9cdecreasing the incidence of precipitation of a lipophilic and/or water labile drug occurring at or near the injection site and/or in the lungs or other organs following parenteral administration.
Neither of the Bodor references mentions the problem of irritation associated with the administration of these water soluble compounds or ulceration associated with their extravasation. Furthermore, neither of the Bodor references teaches or suggests that water soluble cytotoxic or antineoplastic drugs or the water-soluble salts of such drugs when administered with cyclodextrin compounds can significantly decrease ulceration or irritation associated with administration or extravasation of such drugs.
Significantly the Bodor references attribute the precipitation and organ deposition problems associated with parenteral administration of lipophilic drugs to the effects of organic solvents used to solubilized the drug in the parenteral vehicle. The Bodor references additionally state that drugs which are particularly useful in the parenteral composition and methods disclosed therein are those which are relatively insoluble in water but whose water solubility can be substantially improved by formulation with 20 to 50% of the selected cyclodextrin, e.g. HPCD, in water.
Thus it is quite clear that the Bodor references are directed to prevention of the phenomenon of precipitation of insoluble drugs and insoluble drug-carrier complexes. There is no disclosure concerning the prevention of ulceration or irritation or of amounts of the amorphous cyclodextrin useful for the prevention of these two side effects.
The present invention provides a composition of matter comprising an anti-ulceration-effective amount or an anti-irritation-effective amount of an amorphous complex of cyclodextrin and any compound which can cause extravasation-associated ulceration or irritation when injected. In general such compounds are cytotoxic compounds, but the compositions of matter according to the invention are not limited to cytotoxic compounds. For example certain sedative compounds when injected intravascularly (IV) can cause severe ulceration if extravasation occurs. Such sedative compounds include but are not limited to diazepam compounds including diazepam. In addition certain ionotrophic drugs such as dopamine, may lead to ulceration if extravasated or to vascular irritation when injected.
The present invention is useful in the prevention of extravasation-associated ulceration and irritation associated with injection of drugs that are insoluble in water as well as drugs that are soluble in water. It is particularly and unexpectedly effective in prevention of these side effects in the administration of water soluble cytotoxic agents. In particular, the present invention is a composition of matter that marks an improvement in the formulation of cytotoxic agents which are water soluble whereby the tendency of these agents to cause irritation or ulceration when extravasated on injection is substantially eliminated. By combining such water soluble cytotoxic agents with a cyclodextrin compound and preferably an amorphous cyclodextrin such as an alkyl-substituted or hydroxyalkyl-substituted xcex1-, xcex2-, or xcex3-cyclodextrin compound, irritation or ulceration when extravasated is substantially eliminated. Applicant has further discovered that surprisingly the inclusion of an excipient such as mannitol, sorbitol or lactose further improves the performance of the composition in that the reduction in ulceration is even more pronounced than when the drug is used with the cyclodextrin compound alone.
The phenomena of ulceration and irritation should be understood to be a different side effect than the phenomenon of precipitation which is addressed in the Bodor references. The distinction is clearest in the case of cytotoxic agents and particularly in the case of water soluble cytotoxic agents. In general the lipophilic drugs and drug-carrier complexes that Bodor discloses precipitate at the injection site or near to the side of injection, even when they are properly injected intravenously and not extravasated. Thus the fundamental teaching of the Bodor references relates to solubilization of insoluble drugs so that they do not precipitate from the blood stream of a patient into the blood vessels near the site of injection or in more remote capillary beds of distant organs such as the lung.
By contrast the phenomenon of extravasation occurs when the drug either leaks from a blood vessel into the perivascular tissue or is inadvertently injected into the perivascular tissue. When certain drugs are extravasated they cause ulceration. It will therefor be appreciated that extravasation is particularly threatening when the drug is a water-soluble cytotoxic compound. Such water soluble drugs, instead of precipitating and leading to a localized ulceration, tend to disseminate into more distant tissues from the perivascular tissue immediate to the site of injection. This dissemination leads to extensive ulceration and not localized precipitation. Thus for example there are many reported cases in which localized extravasation of the water soluble agent doxorubicin leads to disseminated ulceration of the whole limb of the patient.
Compositions of matter according to the invention comprising an amorphous complex of cyclodextrin and a cytotoxic compound may comprise a variety of different cytotoxic compounds used for a variety of therapeutic purposes. Such compositions according to the invention include an amorphous complex of cyclodextrin and an anti-cancer, anti-neoplastic, anti-fungal antibiotic, anti-bacterial antibiotic or chemical compound. Especially preferred in the compositions according to the invention are those in which the cytotoxic compound is one that is soluble in aqueous solution. Compounds that are soluble in aqueous solution include those in which the active drug is soluble. Also included are those drugs in which the acid complex of the active compound is soluble in water, such as doxorubicin hydrochloride. Additionally, a salt of an active drug formed to render the drug soluble is included in compounds that are soluble in aqueous. solution. Examples of the latter include vincristine sulfate and vinblastine sulfate (the sulfate salts of the active drug) and erythromycin lactobionate (prepared from erythromycin base and lactobiono-xcex4-lactone).
The cytotoxic compound may be a synthetic chemical compound such a nitrogen mustard derivative such as mechlorethamine. The cytotoxic compound may be a plant alkaloid such as vincristine and vinblastine or an alkylating agent such as dacarbazine and streptozocin. The compound may be microbially produced and subsequently purified or partially purified antibiotic. Cytotoxic antibiotics that may be part of the composition according to the invention include those administered as anti-cancer agents, such as the mitomycins including but not limited to mitomycin-c, the bleomycins including but not limited to mixtures predominating in bleomycin A2 and B, daunorubicin, doxorubicin, idarubicin plicamycin and dactinomycin. With respect to the compositions of matter comprising an amorphous complex of cyclodextrin and a cytoxic compound which is a chemotherapeutic anticancer agent, the anticancer agent may be a vessicant or an irritant. Composititons of matter in which the anti-cancer agent is a protein biological response modifier such as interleukin-2 or Tumor necrosis factor are not intended as the anti-cancer agents of the composition according to the invention; however compositions of matter which include such protein biologicaal response modifiers and an anti-neoplastic chemotherapeutic agent are intended as compositions according to the invention.
Other cytotoxic antibiotics that may be part of the composition according to the invention include antifungal antibiotic agents such as amphoteracin B and certain anti-bacterial antibiotics, such as tetracycline and erythromycin that may lead to ulceration if extravasated or to vascular irritation when injected. Additionally, the compositions according to the invention include pharmaceutical compounds which are not administered to achieve a specific cytotoxic effect, but which may also result in extravasation-associated ulceration. Such compounds which may be part of the compositions according to the invention include, for example certain sedative compounds typified by benzodiazapine compounds including but not limited to diazepam.
The compositions of matter according to the invention may also include, in addition to the amorphous complex of cyclodextrin and cytotoxic compound, carriers, bulking agents and other pharmaceutically acceptable excipients such as mannitol, sorbitol, lactose, dextrox and the like. Surprisingly, it has been found that certain chemotherapeutic compounds and such excipients, particularly mannitol, when formulated with cyclodextrin do not cause any significant extravasation when administered to mammalian subjects.
The composition of matter according to the invention may be supplied as a dry powder or as a solution. If the composition of matter is to be injected into a subject it will be rendered sterile prior to injection. Accordingly, the composition of matter according to the invention may be supplied as a sterile cake, plug or powder or as a sterile lyophilized preparation in a sterile vial suitable for the addition of a sterile diluent, or as a sterile liquid solution in a sterile container.
It is an object of the present invention to provide compositions of matter which substantially reduce ulcerationassociated with extravasation caused by compounds which can cause such ulceration comprising an amorphous complex of cyclodextrin and such compound.
Another object of the present invention to provide compositions of matter which substantially reduce ulceration associated with extravasation caused by compounds that are soluble in aqueous solution which can cause such ulceration comprising an amorphous complex of cyclodextrin and such compound that is soluble in aqueous solution.
It is a further object of the present invention to provide compositions of matter which substantially reduce ulceration associated with extravasation caused by cytotoxic drugs which can cause such ulceration comprising an amorphous complex of cyclodextrin and a cytotoxic drug.
It is another object to the invention to provide compositions of matter which substantially reduce ulceration associated with extravasation caused by antibiotics which can cause such ulceration comprising an amorphous complex of cyclodextrin and such an antibiotic.
It is yet another object to the invention to provide compositions of matter which substantially reduce ulceration associated with extravasation caused by antineoplastic drugs which can cause such ulceration comprising an amorphous complex of cyclodextrin and such antineoplastic drugs.
It is an object of the present invention to provide compositions of matter which substantially reduce ulceration associated with extravasation caused by compounds which can cause such ulceration comprising an ulceration reducing amount of an amorphous complex of cyclodextrin and such compound.
Another object of the present invention to provide compositions of matter which substantially reduce ulceration associated with extravasation caused by compounds that are soluble in aqueous solution which can cause such ulceration comprising an ulceration-reducing amount of anamorphous complex of cyclodextrin and such compound that is soluble in aqueous solution.
It is a further object of the present invention to provide compositions of matter which substantially reduce ulceration associated with extravasation caused by cytotoxic drugs which can cause such ulceration comprising an ulceration-reducing amount of an amorphous complex of cyclodextrin and a cytotoxic drug.
It is another object to the invention to provide compositions of matter which substantially reduce ulceration associated with extravasation caused by antibiotics which can cause such ulceration comprising an ulceration-reducing amount of an amorphous complex of cyclodextrin and such an antibiotic.
It is yet another object to the invention to provide compositions of matter which substantially reduce ulceration associated with extravasation caused by antineoplastic drugs which can cause such ulceration comprising an ulceration-reducing amount of an amorphous complex of cyclodextrin and such an antineoplastic agent.
Still another object of the invention is to provide a method for reducing the likelihood of ulceration in subjects in need of parenteral treatment with compounds that if extravasated have the potential for causing ulceration, comprising administering to such subjects a preparation comprising at least one compound that if extravasated has the potential for causing ulceration and an anti-ulceration-effective amount of cyclodextrin or amorphous cyclodextrin.
Yet still another object of the invention is to provide a method for reducing the likelihood of irritation in subjects in need of parenteral treatment with compounds that when administered parenterally, particularly intravenously, have the potential for causing irritation, comprising administering to such subject a preparation comprising at least one compound that has the potential for causing irritation and an anti-irritation-effective amount of cyclodextrin or amorphous cyclodextrin.
By cyclodextrin is meant xcex1-, xcex2-, or xcex3-cyclodextrin. Cyclodextrins are described in detail in Pitha et al., U.S. Pat. No. 4,727,064 which is incorporated herein by reference. Cyclodextrins are cyclic oligomers of glucose; these compounds form inclusion complexes with any drug whose molecule can fit into the lipophile-seeking cavities of the cyclodextrin molecule.
By amorphous cyclodextrin is meant non-crystalline mixtures of cyclodextrins wherein the mixture is prepared from xcex1-, xcex2-, or xcex3-cyclodextrin. In general the amorphous cyclodextrin is prepared by non-selective additions, especially alkylation of the desired cyclodextrin species. Reactions are carried out to yield mixtures containing a plurality of components thereby preventing crystallization of the cyclodextrin, various alkylated and hydroxyalkyl-cyclodextrins can be made and of course will vary, depending upon the starting species of cyclodextrin and the addition agent used. Among the amorphous cyclodextrins suitable for compositions according to the invention are hydroxypropyl, hydroxyethyl, glucosyl, maltosyl and maltotrosyl derivatives of xcex2-cyclodextrin, carboxyamidomethyl-xcex2-cyclodextrin, carboxymethyl-xcex2-cyclodextrin, hydroxypropyl-xcex2-cyclodextrin and diethylamino-xcex2-cyclodextrin. In the compositions according to the invention hydroxy-xcex2-cyclodextrin is preferred. The substituted xcex3-cyclodextrins may also be uirable, including hydroxyproply, hydroxyethyl, glucosyl, maltosyl and maltotriosyl derivatives of xcex3-cyclodextrin.
By cyclodextrin compound is meant cyclodextrin and amorhpous cyclodextrin.
The term xe2x80x9cpharmaceutically accepted or acceptable excipientxe2x80x9d means an ingredient used in a pharmaceutical preparation which does function as an active agent. Such pharmaceutically acceptable excipients are used for various purposes, such as stabilizers, buffers, suspending agents, carriers and the like and are listed and described in a number of texts including for example, the British Pharmacopeia, the Japanese Pharmacopeia and the United States Pharmacopeia XXII and National Formulary XVII and supplements thereto. Suitable excipients for injectable pharmaceutical compositions are typified by non-reducing sugars or sugar alcohols such as mannitol and sorbitol. Glucose, and lactose may also be used as excipients.
By dactinomycin (actinomycin-D) is meant an antibiotic substance belonging to the actinomycin complex produce by several Streptomyces species having the elemental composition of C62H86N12O16, and molecular weight 1255.47. It is sold under the trade name Cosmegen (Merck, Sharp and Dohme) as a sterile lyophilized powder including dactinomycin and mannitol.
By mithramycin is meant an antibiotic substance identified as aurelic acid, produce by several Streptomyces species including Streptomyces argillaceus and Streptomyces tanashiensis, having the elemental composition of C52H72O24, chemical formula [2S-{2xe2x88x9d,3xcex2(1R*.3R*.4S*)]]-6-{(2,6-Dideoxy-3-O-(2,6-dideoxy-xcex2-D-arabino-hexopyranosyl-xcex2-D-arabino-hexopyranosyl]oxy]-2-[O-2,6-dideoxy-3-C-methyl-xcex2-D-ribo-hexopyranosyl-(1-4)-O-2,6-dideoxy-xe2x88x9d-D-lyxo-hexopyranosyl-(1-3)-2,6-dideoxy-xcex2-D-arabino-hexopyranosyl)oxy]-3-(3,4dihydrox-1-methyl-2oxopentyl)-3,4-dihydro-8,9-dihydroxy-7-methyl-1(2H)-anthracenone molecular weight 1085.18. It is also know under the generic name plicamycin. It is sold under the trade name Mithracin (Miles, Inc. Pharmaceutical Division) as a sterile freeze dried preparation for intravenous administration including mithramycin and mannitol and sufficient disodium phosphate to adjust to pH 7.
By mitomycin-C is meant one of a group of anti-neoplastic antibiotics substances mitomycin-A, -B, and -C produced by Streptomyces caespitosus (griseovanaceseus). Mitomycin-D has also been isolated from Streptomyces verticillatus. Mitomycin-C has the elemental composition of C15H18N4O6 and chemical formula [1aR]-6-amino-8-[[aminocarbonyl)oxy]methyl]-1, 1a,2,8,8a,8b-hexahydro-8a-methoxy-5-methylazirinol[2xe2x80x2,3xe2x80x2:3,4]pyrrolo[1,2-a]indole-4,7-dione. It is sold under the trade name Mutamycin (Bristol-Myers Oncology Division, Bristol-Myers Squibb Company) as a sterile powder including mannitol.
By N-methyl mitomycin-C is meant an anti-bacterial anti-neoplastic substance, also called porfiromycin, isolated from a Streptomyces ardus fermentation broth and also isolated from Streptomyces verticillatus. N-methyl mitomycin-C has the elemental composition of C16H20N4O5 and chemical formula 6-amino-8-[[aminocarbonyl)oxy]methyl]-1,1a,2,8,8a,8b-hexahydro-8a-methoxy-1,5-dimethylazirinol[2xe2x80x2,3xe2x80x2:3,4]pyrrolo[1,2-a]indole-4, 7-dione.
By alkaloid is meant an amine containing compound originally isolated from a plant which may be commercially produced by extraction from plant material and purification, or by synthetic or semi-synthetic means.
By vincaalkaloid is meant alkaloid compounds originally isolated form the plant Vinca rosea Linn (Catharanthus roseus or Apocynaceae), and Vinca minor. These compounds are useful in several therapeutic categories including anti-neoplastics and vasodialators. Among these compounds are vinblastine, vincamine, vincine, vincaminine, vincinine, vincristine and the synthetic dimer of vinblastine, vindesine.
By vincristine is meant a vincaalkaloid identified as 22-Oxoyincaleukoblastine or leurocristine acid, originally isolated from the plant Vinca rosea Linn, having the elemental composition of C46H56N4O10, and molecular weight 824.94, and its sulfate salt having the elemental composition C46H56N4O14S and molecular weight 923.04. The sulfate salt of vincristine is sold under the trade name Oncovin (Eli Lilly and Company) as a sterile liquid containing vincristine, mannitol, methylparaben, propylparaben and water with acetic acid and sodium acetate added for pH control.
By vinblastine is meant a vincaalkaloid identified as Vincaleukoblastine, originally isolated from the plant Vinca rosea Linn, having the elemental composition of C46H56N4O9, and molecular weight 811.00, and its sulfate salt having the elemental composition C46H60N4O13S and molecular weight 909.10. The sulfate salt of vinblastine is sold under the trade name Velban (Eli Lilly and Company) as a sterile lyophilized plug containing no excipients.
By xe2x80x9canti-ulceration-effective amountxe2x80x9d means an amount of a substance which when combined with a compound, cytotoxic drug, antibiotic or alkaloid, with or without an excipient and administered to a subject, significantly reduces the extent of ulceration that occurs, if any, compared to the extent of ulceration caused by the same amount of compound, cytotoxic drug, antibiotic or alkaloid, with or without an excipient when administered alone to a subject. Included in the phenomena defined herein as ulceration or ulcer are those phenomena usually associated with vesicants. See, Chapter 8 xe2x80x9cExtravasationxe2x80x9d in Cancer Chemotherapy, A Reference Guide, Linda Tenenbaum, W. B. Saunders Company, Harcourt Brace Jovanovich, Inc Philadelphia (1989); and Chapter 5 xe2x80x9cCommon Toxicitiesxe2x80x9d in Cancer Chemotherapy Handbook, Robert T. Dorr and William L. Fritz, Elsevier, N.Y. The term ulceration or ulcer is not intended to include gastrointestinal, duodenal or intestinal irritation or ulceration associated with the oral administration of a number of oral analgesic and anti-inflammatory drugs such as indomethacin
By vesicant is meant a chemotherapeutic agent which is topically toxic. If inadvertantly delivered outside of a vein, a vesicant has the potential to cause pain, cellular damage including cellulitis, tissue destruction (necrosis) with formation of a sore or ulcer and sloughing of tissues that may be extensive and require skin grafting. Examples of anti-cancer chemotherapeutic agents that are vesicants include but are not limited to Amsacrine, Dactinomycin, Daunorubicin, Doxorubicin, Idarubicin, Mechlorethamine, Mitomycin C, Vinblastine, Vincristine and Vindesine.
By anti-irritation-effective amount means an amount of a substance which when combined with a compound, cytotoxic drug, antibiotic or alkaloid, with or without an excipient and administered to a subject, significantly reduces the extent of irritation that occurs, if any, compared to the extent of irritation caused by the same amount of compound, cytotoxic drug, antibiotic or alkaloid, with or without an excipient when administered alone to a subject. Included in the phenomena defined herein as irritation are those phenomena usually associated with irritants. See, Chapter 8 xe2x80x9cExtravasationxe2x80x9d in Cancer Chemotherapy, A Reference Guide, Linda Tenenbaum, W. B. Saunders Company, Harcourt Brace Jovanovich, Inc Philadelphia (1989) and Chapter 5 xe2x80x9cCommon Toxicitiesxe2x80x9d in Cancer Chemotherapy Handbook, Robert T. Dorr and William L. Fritz, Elsevier, N.Y. The term irritation is not intended to include gastrointestinal, duodenal or intestinal irritation or ulceration associated with the oral administration of a number of oral analgesic and anti-inflammatory drugs such as indomethacin.
By irritant is meant a chemotherapeutic agent that may produce pain and inflammation at the administration site or along the path of the vein (phlebitis) by which it is administered. Examples of anti-cancer chemotherapeutic agents which are irritants include but are not limited to Carmustine, Dacarbazine, Etoposide, Plicamycin, Etoposice, Streptozocin and Tenoposide.
By aqueous solution is meant solutions comprised of at least 90% water (weight/volume).
By cytotoxic is meant having the property of killing cells at low molar concentrations.
By antibiotic is meant compounds produced by microorganisms, and derivatives of such. compounds, which are capable at concentrations above a particular threshold concentration of killing other microorganisms and/or cells including mammalian cells.
By anti-cancer antibiotic is meant an antibiotic which is capable of killing cancerous cells.
By aminoglycoside antibiotic is meant an antibiotic compound containing nitrogen, usually in the form of at least one amino group wherein the compound also contains at least one glycoside bond to a sugar or saccharide moiety.
By daunorubicin is meant an antibiotic of the rhodomycin group, originally isolated from fermentation broths of Streptomyces peuicetius or Streptomyces coentleonibidus and its acid complexes particularly its hydrochloride complex. Daunorubicin is a glycoside formed by a tetracyclic aglycone daunomycinone and an amino sugar daunosamine. Daunorubicin has the elemental composition of C27H29NO10 and chemical formula 8-Acetyl-10-[3-amino-2,3,6-tri-deoxy-xcex1-L-lyxo-hexopyranosyl)oxy]-7,8,9,10-tetrahydro-6,8,-l 11-trihydroxy-1-methoxy-5,12-naphthacenedione, and molecular weight 527.51. Daunorubicin is sold under the trade name Cerubidine (Wyeth Ayerst Laboratories) as a sterile lyophilized powder with mannitol.
By doxorubicin is meant 14-hydroxydaunomycin a derivative of daunorubicin, and its acid complexes particularly its hydrochloride complex) having the elemental composition C27H29NO11 and chemical formula 10-[(3-amino-2,3,6-tri-deoxy-xcex1-L-lyxo-hexopyransoyl)oxy]-7,8,9,10-tetrahydro-6,8,-11-trihydroxy-8-(hydroxyacetyl)-1-methyoxy-5,12-naphthacenedione and molecular weight 543.54. Doxorubicin HCL is sold as a generic drug by various manufacturers as a sterile lyophilized powder with mannitol and as a sterile solution of doxorubicin hydrochloride in sterile water for injection made iso-osmotic with sodium chloride and dextrose or other suitable added excipient.
By bleomycins is meant a group of related glycopeptide antibiotic substances including bleomycin-A, -B and -C and their components. Bleomycins are isolated from Streptomyces verticillatus. The bleomycins differ from one another in their terminal amines and show varying biological activity. Bleomycin A2 is the main component of the bleomycin employed clinically as an anti-cancer antibiotic. Bleomycin-A2 has the elemental composition of C55H84N17O21S3 and chemical formula N1-[3-(dimethylsulfonio)-propyl]bleomycinamide. Also included in this definition are the sulfate salts of the bleomycins.
By bleomycin is meant a mixture of basic cytotoxic glycopeptides produced by the growth of Streptomyces verticillatus or by other means and the sulfate salts thereof. In general HPLC analysis of bleomycin according to the definition shows the following contents, in order of elution as described in United States Pharmacopeia XXII: bleomycinic acid, bleomycin A2, bleomycin A5, bleomycin B2 and bleomycin B4. In a preferred embodiment of the invention Bleomycin as used herein conforms to the description of Bleomycin Sulfate in the United States Pharmacopeia XXII in that the content of the sulfate salts of bleomycin A2 is between 55% and 70%, bleomycin B2 is between 25% and 32% and bleomycin B4 is not more than 1%; and the combined percentage of the sulfate salts of bleomycins A2 and B2 is not less than 85%. A mixture of bleomycin A2 and bleomycin B2 (or their sulfate salts), wherein the concentration of bleomycin B2 is no less than 25% is also within the present definition of bleomycin. Bleomycin is sold under the trade name Blenoxane (Bristol-Myers Oncology Division, Bristol-Myers Squibb Company) as a sterile powder including mannitol.
By diazepam is meant is meant a benzodiazepine derivative having the chemical formula 7-chloro-1,3(dihydro-1-methyl-5-phenyl-2H-1,4-benzodiazepin-2-one and having a molecular weight of 284.7. Diazepam is sold under the tradename Valium (Roche Products, Inc.) and includes diazepam compounded with propylene glycol, ethyl alcohol, sodium benzoate and benzoic acid and benzyl alcohol.
Cytotoxic agents that are soluble in aqueous solution include but are not limited to antineoplastic compounds chosen from the following Table A. The solubilities of the compounds listed in Table A are compiled from a number of references including The Merck Index 10th Edition, the Physicians Desk Reference (1992 edition), and The Cytotoxics Handbook (Radcliff Medical Press, Oxford 1993) which are incorporated herein by reference.
Bearing in mind the above described definitions, the present invention is for novel compositions of matter comprising an ulceration-reducing or irritation-reducing amount of a cyclodextrin compound and a cytotoxic compound. In a preferred embodiment the cyclodextrin is a substituted amorphous cyclodextrin, such as an alkyl or hydroxy alkyl substituted, including hydroxypropyl, hydroxyethyl, glucosyl, maltosyl and maltotrosyl derivatives of xcex2-cyclodextrin or xcex3-cyclodextrin and the cytotoxic agent is one that is soluble in aqueous solution.
In general, the invention provides a composition of matter comprising an amorphous complex of cyclodextrin and any compound which can cause extravasation-associated ulceration or irritation when injected. While many such compounds are cytotoxic compounds, the compositions of matter according to the invention are not limited to cytotoxic compounds. For example certain sedative compounds when injected intravascualrly (iv) can cause severe ulceration if extravasation occurs. Such sedative compounds include but are not limited to diazepam compounds including diazepam.
Compositions of matter comprising an amorphous complex of cyclodextrin and a cytotoxic compound according to the invention may comprise a variety of different cytotoxic compounds used for a variety of therapeutic purposes. Such compositions according to the invention include an amorphous complex of cyclodextrin and an anti-cancer, anti-neoplastic, anti-fungal antibiotic, anti-bacterial antibiotic or chemical compound.
With respect to the compositions of matter comprising an amorphous complex of cyclodextrin and a cytotoxic compound which is a chemotherapeutic anticancer agent, the anticancer agent may be classified as a vesicant or an irritant. Examples of anti-cancer chemotherapeutic agents that are vesicants include but are not limited to Amsacrine, Dactinomycin, Daunorubicin, Doxorubicin, Idarubicin, Mechlorethamine, Mitomycin C, Vinblastine, Vincristine and Vindesine. Examples of anti-cancer chemotherapeutic agents which are irritants include but are not limited to Carmustine, Dacarbazine, Etoposide, Plicamycin, Etoposide, Streptozocin and Tenoposide. The effects of such agents on patients are found in the following Table B:
In general, the composition of matter according to the invention will comprise a sufficient amount of the compound to exert its desired pharmacological effect when administered IV, whether it is for example sedation, anti-fungal activity, anti-neoplastic activity, and an amount of cyclodextrin compound sufficient to significantly reduce the extent of ulceration or irritation that would occur if a like amount of the compound were extravasated or administered IV without extravasation in the absence of the cyclodextrin compound. If the anticancer compound is a vesicant the composition of matter according to the invention will comprise a sufficient amount of the anticancer compound to exert its desired cytotoxic effect against targeted cancer cells and an anti-ulceration-effective amount of cyclodextrin, with or without an excipient. Likewise, if the anticancer compound is an irritant, the composition of matter according to the invention will comprise a sufficient amount of the anticancer compound to exert its desired cytotoxic effect against target cancer cells and anti-irritation-effective amount of cyclodextrin with or without an excipient.
The anti-cancer chemotherapeutic compounds that may comprise the composition according to the invention will be any anticancer chemotherapeutic compound that causes irritation, as defined herein, or ulceration, as defined herein, upon extravasation. The compound may be a synthetic chemical compound such a nitrogen mustard derivative for example mechlorethamine. The antineoplastic compound may be a plant alkaloid. With respect to such plant alkaloids, taxol, a chemical compound derived from the bark of the Pacific Yew tree, and pharmacologically active related compounds are contemplated. Also contemplated are water soluble compounds related to taxol such as taxotrere. While taxol is not water soluble, ulcerative activity caused by this anti-neoplastic compound may be significantly reduced by administration with hydroxypropyl-xcex2-cyclodextrin and it is believed that further improvement in anti-ulcerativie effect will be obtained with amorphous xcex3-cyclodextrins Also contemplated in the compositions according to the invention are the vinca alkaloids. Such vinca alkaloids as vincristine and vinblastine and vindisine are particularly strong vesicants.
Also among the anti-cancer chemotherapeutic compounds that may comprise the composition according to the invention are alkylating agents which are used as anti-cancer chemotherapeutics such as dacarbazine and streptozocin.
The composition according to the invention may comprise a complex of cyclodextrin and a microbial produced antibiotic compound which is subsequently purified or partially purified. Cytotoxic antibiotics that may be part of the composition according to the invention include those administered as anti-cancer agents, such as the mitomycin including but not limited to mitomycin-c, the bleomycins including but not limited to mixtures predominating in bleomycin A2 and B, daunorubicin, doxorubicin, plicamycin and dactinomycin. All of the forgoing are soluble in aqueous solution.
Anti-cancer agents which are protein biological response modifier such as interleukin-2 or Tumor Necrosis Factor are not intended as the anti-cancer agents of the compositions according to the invention since they do not cause ulceration or irritation as defined herein resulting from extravasation; however compositions of matter which include such protein biological response modifiers and an anti-neoplastic chemotherapeutic agent which does cause extravasation associated irritation or ulceration are intended as compositions according to the invention.
The composition according to the invention may comprise a complex of cyclodextrin and other cytotoxic anti-fungal antibiotic agents such as amphoteracin B.
Additionally, the compositions according to the invention include pharmaceutical compounds which are not administered to achieve a specific cytotoxic effect, but which may also result in extravasation-associated ulceration. Such compounds which may be part of the compositions including cyclodextrin according to the invention include, for example certain sedative compounds typified by benzodiazapine compounds including but not limited to diazepam. In this instance, the composition according to the invention comprises an amount of the compound sufficient to exert the desired pharmacological effect when administered iv and an anti-ulceration or anti-irritation effective amount of the cyclodextrin compound.
The compositions of matter according to the invention may also include, in addition to the complex of cyclodextrin and a chemotherapeutic compound, carriers, bulking agents and other pharmaceutically acceptable excipients such as mannitol, sorbitol, lactose, sucrose and the like. Surprisingly, it has been found that chemotherapeutic compounds and such excipients, particularly mannitol, when formulated with cyclodextrin do not cause any significant ulceration if extravasated when administered to mammalian subjects.
The cyclodextrin of the compositions according to the invention may be xcex1, xcex2, or xcex3-cyclodexrin. xcex1-cyclodextrin contains six glucopyranose units; xcex2-cyclodextrin contains seven glucopyranose units; and xcex3-cyclodextrin contains eight glucopyranose units. The molecule is believed to form a truncated cone having a core opening of 4.7-5.3 xc3x85, 6.0-6.5 xc3x85 and 7.5-8.3 xc3x85 in xcex1-, xcex2-, or xcex3-cyclodextrin respectively. The composition according to the invention may comprise a mixture of two or more of the xcex1-, xcex2-, or xcex3-cyclodextrins. Usually, however the composition according to the invention will comprise only one of the xcex1-, xcex2-, or xcex3-cyclodextrins. The particular xcex1-, xcex2-, or xcex3-cyclodextrin to be used with the particular cytotoxic compound to form the compositions according to the invention may be selected based on the known size of the molecule of the cytotoxic compound and the relative size of the cavity of the cyclodextrin compound. Generally if the molecule of the cytotoxic compound is relatively large, a cyclodextrin having a larger cavity is used to make the composition according to the invention. Furthermore, if the cytotoxic compound is administered with an excipient it may be desirable to use a cyclodextrin compound having a larger cavity in the composition according to the invention.
The unmodified xcex1-, xcex2-, or xcex3-cyclodextrins are less preferred in the compositions according to the invention because the unmodified forms tend to crystalize and are relatively less soluble in aqueous solutions. More preferred for the compositions according to the invention are the xcex1-, xcex2-, and xcex3-cyclodextrins that are chemically modified or substituted. Chemical substitution at the 2,3 and 6 hydroxyl groups of the glucopyranose units of the cyclodextrin rings yields increases in solubility of the cyclodextrin compound.
Most preferred cyclodextrins in the compositions according to the invention are amorphous cyclodextrin compounds. By amorphous cyclodextrin is meant non-crystalline mixtures of cyclodextrins wherein the mixture is prepared from xcex1-, xcex2-, or xcex3-cyclodextrin. In general, the amorphous cyclodextrin is prepared by non-selective alkylation of the desired cyclodextrin species. Suitable alkylation agents for this purpose include but are not limited to propylene oxide, glycidol, iodoactamide, chloroacetate, and 2-diethylaminoethlychloride. Reactions are carried out to yield mixtures containing a plurality of components thereby preventing crystallization of the cyclodextrin. various alkylated cyclodextrins can be made and of course will vary, depending upon the starting species of cyclodextrin and the alkylating agent used. Among the amorphous cyclodextrins suitable for compositions according to the invention are hydroxypropyl, hydroxyethyl, glucosyl, maltosyl and maltotrosyl derivatives of xcex2-cyclodextrin, carboxyamidomethyl-xcex2-cyclodextrin, carboxymethyl-xcex2-cyclodextrin, hydroxypropyl-xcex2-cyclodextrin and diethylamino-xcex2-cyclodextrin. In the compositions according to the invention hydroxypropyl-xcex2-cyclodextrin is preferred although the xcex1- or xcex3-analogs may also be suitable. The particular alkylated xcex1-, xcex2-, or xcex3-cyclodextrin to be used with the particular cytotoxic compound to form the compositions according to the invention will be selected based on the size of the molecule of the cytotoxic compound and the relative size of the cavity of the cyclodextrin compound. As with the unsubstituted cyclodextrins mentioned above, it may be advantageous to use alkylated cyclodextrin having a larger cavity when the composition according to the invention also includes an excipient. The use of a particular xcex1-, xcex2-, or xcex3-cyclodextrin with a particular cytotoxic compound or cytotoxic compound and excipient in the compositions according to the invention may of course be optimized based on the effectiveness in reducing ulceration or irritation.
Another significant factor in determining the anti-ulcerative and anti irritation effects of complexes of substituted cyclodextrins and cytotoxic drugs is the degree of substitution of substituent groups in the cyclodextrin molecule, whether it is xcex1-, xcex2-, or xcex3-cyclodextrin. By degree of substitution is meant the number of substituent molecules per molecule of cyclodextrin. In the composition according to the invention a higher average degree of substitution of substituent groups in the cyclodextrin molecule is believed to be preferable. Such substituent groups are exemplified by those mentioned in the paragraph above. A degree of substitution in the range of about 4 to about 10 for hydroxypropyl substituents may be effective with mitomycin-c and doxorubicin. A degree of substitution in the range of about 5 to about 9 is preferred and is expected to be anti-ulceration effective for compositions including both water soluble anti-neoplastic agents such as those mentioned herein above and water insoluble antineoplastic agents such as taxol.
As mentioned above, the compositions of matter of the invention comprise a cytotoxic compound and cyclodextrin. The relative amounts of cytotoxic compound and cyclodextrin will vary depending upon the relative toxicity of the compound and the effect of the cyclodextrin on the compound. In general, the ratio of the weight of cytotoxic compound to the weight of cyclodextrin compound will be in a range between 1:20 and 1:5000. Within this range, the ulcerative effects of many cytotoxic compounds will be significantly reduced when the ratio of the weight of cytotoxic compound to the weight of cyclodextrin compound is in a range between 1:50 and 1:2000. A weight to weight ratio in a range of 1:50 to 1:2000 and more preferably in a range of 1:50 to 1:800 cf cytotoxic chemotherapeutic compound to cyclodextrin are believed to be effective for a number of vesicant anti-cancer chemotherapeutics. For example Mitomycin in a ratio of between 1:100 to 1:300 (drug to cyclodextrin) significantly reduces the extent of ulceration clue to intradermally deposited mitomycin C. When mitomycin C in a weigh to weight ratio with xcex2-hydroxypropyl cyclodextrin of 1:160 was injected intradermally in a mammalian subject the lesion resulting from the injection was about one third the size of the lesion cause by intradermal injection of the same amount of mitomycin C without the cyclodextrin compound. Furthermore when mitomycin-C together with the excipient mannitol in a weight to weight ratio with xcex2-hydroxypropyl cyclodextrin of 1:400 (mitomycin: xcex2-hydroxypropyl cyclodextrin) was injected intradermally in a mammalian subject, the lesion resulting from the injection was eliminated entirely in 80% of the test subjects, and in the remaining test subjects the lesion was about one tenth the size of the lesion cause by intradermal injection of the same amount of mitomycin C and mannitol without the cyclodextrin compound.
The compositions of matter according to the invention may by supplied as a powder comprising the active pharmaceutical compound and cyclodextrin compound. If the composition is to be administered parenterally, for example iv, the composition of matter will be rendered sterile prior to such administration. Any of the several known means for rendering such pharmaceutical preparations sterile may be used so long as the active pharmaceutical compound is not inactivated. If the active pharmaceutical compound is heat stable, the composition of matter according to the invention may be heat sterilized. If the cytotoxic compound is not heat stable but is not photodegraded the composition may be sterilized by exposure to ultraviolet light. Alternatively, the composition of matter if in a powder form may be gas sterilized using for example ethylene oxide gas. In another alternative, the composition of matter according to the invention may be filter sterilized using a 2 micron filter. If the composition of matter is a aqueous liquid, it may be filled in a sterile container and supplied as a sterile liquid ready for further dilution or injection neat Alternatively such sterile liquids may be freeze dried or lyophilized in a sterile container and capped.
In general the compositions of matter according to the invention will be made by dissolving the cyclodextrin in water and adding the active compound to the aqueous cyclodextrin solution. Excipients, if any are desired may be added with or subsequent to adding the active compound. The resulting solution may be sterilized using any of the known methods appropriate to preserving the active compound. Alternatively, the components may be sterilized by any of the known methods appropriate to preserving the active compound prior to mixing in water an may be mixed using sterile equipment and technique. The solution may be lyophilized in sterile containers and capped. Prior to use the lyophilized composition of matter may be reconstituted using sterile water for injection.
It will be understood that the compositions of matter according to the invention provide novel methods of controlling and reducing the incidence of ulceration associated with extravasation and irritation associated with intravenous administration of many pharmaceutical compounds. The compositions of matter according to the invention provide a method for reducing the likelihood of ulceration in subjects in need of parenteral treatment with compounds that if extravasated have the potential for causing ulceration, by administering to such subjects a preparation comprising at least one compound that if extravasated has the potential for causing ulceration and an anti-ulceration-effective amount of cyclodextrin or amorphous cyclodextrin. Furthermore, the compositions according to the invention provide a method for reducing the likelihood of irritation in subjects in need of parenteral treatment with compounds that when administered parenterally, particularly intravenously, have the potential for causing irritation, by administering to such subject a preparation comprising at least one compound that has the potential for causing irritation and an anti-irritation-effective amount of cyclodextrin or amorphous cyclodextrin.
It will be understood that the present invention provides both compositions of matter and methods for the substantial reduction in injuries caused as a result of extravasation. While it is heretofore known that compositions of amorphous cyclodextrin and compounds that are not soluble in water because they are lipophilic have the property of reducing precipitation of compounds at or near the injection site, the heretofore known compositions and methods fail to make any observation on the effect of extravasated compounds, or the amounts of amorphous cyclodextrin needed to prevent the ulcerative effects of such extravasated compounds.
Accordingly, the present invention is directed to compositions comprising anti ulceration-effective amounts of amorphous cyclodextrin and compounds that otherwise cause ulceration when extravasated. Such compounds may be soluble in aqueous solution or alternatively may be lipophilic and as a result tend to precipitate in aqueous solutions. Since amorphous cyclodextrins are taught in the art to solubilize compounds that are not soluble in water, it is surprising, and heretofore unobserved and unreported that compositions of matter comprising amorphous cyclodextrin and such insoluble compounds, which have been rendered soluble by complexation with cyclodextrin do not lead to ulceration when extravasated. This observation is especially surprising because water soluble cytotoxic compounds frequently cause ulceration when extravasated, and it would be expected that lipophilic cytotoxic compounds rendered soluble by complexation with cyclodextrin would similarly remain cytotoxic.
Even more unexpected is the effect of forming complexes with cyclodextrin compounds on ulceration associated with extravasation using cytotoxic compounds that are soluble in aqueous solution and which are not expected to precipitate at or near the site of injection. Indeed, the literature on extravasation toxicity indicates that the problem of toxicity associated with extravasation of water soluble compounds is exacerbated by the solubility of these compounds. Such water soluble toxic compounds rather than precipitating appear to spread throughout the limb when extravasated. It is thus unexpected that the ulcerative toxicity of such compounds would be curtailed by complexation with a cyclodextrin compound or that complexation of such compounds that are soluble in aqueous solution with a cyclodextrin compound would occur at all.
The invention will be better understood from the following examples which are intended to be merely illustrative of the invention and are not intended to be limiting.